function collectObserver (observerObj, option, ctx) {   
    Object.keys(option).forEach(function (prop) {  
        if (typeof option[prop] !== 'object' || !option[prop]) return false;
        if (option[prop].observer) {
            if (typeof option[prop].observer === 'string') {
                observerObj[prop] = ctx.methods[option[prop].observer];
            } else {
                observerObj[prop] = option[prop].observer;
            }
        }              
    });
    return observerObj;   
}

module.exports = collectObserver;